Use a multi-selection to add Labels/Members on a Card
(Project Manager & Manage Deals) 

Step 1
-
Inside a board click on Multi-Selection button to activate. 

Step 2
-
Select the cards and click on the label user
to add on the selected card.

Member associated.

Step 3
-
Select the cards and click on the label color
to add on the selected card. 

Label associated.